Aromatherapyuses essential oils (concentrated extracts from the roots, leaves, seeds, or blossoms of plants) to promote healing. The oils can be inhaled, massaged into the skin or (in rare cases) taken by mouth, and each has a specific purpose: Some are used to treat inflammation or infections; others are used to promote relaxation. Studies suggest aromatherapy might reduce pain, depression, and anxiety, but more research is needed to fully determine its uses and benefits.